thanks Funbrunette.Actually NASA has just discovered a 10th planet.
Astronomers in the United States have announced the discovery of the "10th planet" to orbit our Sun.
The largest object found in our Solar System since Neptune in 1846, it was first seen in 2003 - but important details have only now been confirmed.
Designated 2003 UB313, it is about 3,000km across - a world of rock and ice and somewhat larger than Pluto.
Scientists say it is three times as far away as Pluto, in an orbit at an angle to the orbits of the main planets.
Astronomers think that at some point in its history, Neptune probably flung the small world into its highly inclined 44-degree orbit.
more details here